Electric switch.



No. 697,!63. Patented Apr. 8, I902.

G. B. PAINTER.

ELECTRIC SWITGH'.

(Application filed m 31, 1901.)

(No Model.)

Wilnesses; Inventorv 6M7 g/wwf GeorgeBPa'mfer' uuuuuuuu etus co. mYmJmo" WASNINGTDN, B4 c,

UNrrnD STATES PATENT OFFICE.

GEORGE I3. PAINTER, OE SCIIENEOTADY, NEl V YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

ELECTRIC SWITCH.

srncrrrcarreu forming part of Letters Patent No. 697,163, dated April 8, 1902. Application filed May 31, 1901. Serial No. 62,581. (No model.)

To a. w/tont it may concern.-

Be it known that I, GEORGE E. PAINTER, a citizen of the United States, residing at Schenectady, county of Schenectady and State of New York, have invented certain new and useful Improvements in Electric Switches, (Case No. 1,8424 of which the following is a specification.

This invention relates to the construction of movableswitch-pieces of electric switches, and has its most important application in connection with the standard Edison key-type incandescent-lamp sockets, which are provided with a switch for making and breaking r5 the circuit of the lamp. This kind of electric switch comprises a rotatable spindle, to which is attached by a lost-motion connection an oblong switch contact or cam, which cam in the closed position of the switch electrically connects a screw-threaded contact-sleeve, which retains the threaded contact-base of alamp with a spring which forms the other circuit-terminal. It is obvious that with such a construction the loosely-mounted oblong contact-piece when rotated by the spindle from its closed position will b polled by the spring-terminal to lore circuit with a snap action to prevent th to mation of arcs, which would otherwise bur and seriously injure theifswitch The end of the spindle onjwhichthe'c'ontactv piece is loosely mounted is itselfso mounted that the spindle can have freeve'rtical movement in order that when the contact-piece is first movedTso thatits upper angular edge abuts against the threaded sleeve the spindle can be pressed downwardly to permit the upper end-ofjthe'contact-piece to assume its final positiousqiiarely against the sleeve, the

0 lower end ofthecontact-piece bearing continuou'sl against the spring-terminal.

' vice in which the present invention rably-embodied is substantially the *thatijust described, and the invenrelates to the mode of construc- "entact-piece and spindle. In the described the contact-piece has a ifforation for the passage of the ofthe spindle, and is also formed with a so transversejgroove or slot 'on one side, the

wallso'f which slot are engaged by a pin carried with lost motion by the spindle, so that the contact-piece is rotated when the spindle is manipulated. In some cases the spindle has been formed with an integral projection, 55 which was struck up near its ends and which took the place of the pin above described. Ever since the invention of the standard Edison socket, however, although other changes have been made, the above-described construction of the contact-piece itself has been adhered to and many millions of lamp-sockets have been made in accordance with that invention, notwithstanding that serious disadvantages have always attended the use of a switch-cam of this construction. These defects will now be explained.

Practical conditions require that the threaded metal sleeve adapted for the reception of the lamp-base shall be constructed of brass, and hitherto it has been believed to be necessary to construct the contact-piece of brass as well. The contact-piece must be a good conductor of electricity, and yet it cannot be made of copper, of whichn etal contact-pieces 7 5 of OthersWitches are generally composed, be-

" oause'this contactpieoe or cam is subjected to an,unusnal' amount'ofwear and copper is too soft forthe purpose. In fact, the chief difficultiesencountered in this art are due to the fact that the various parts of the switch are liable to be worn out by the thousands of operations to which they are subjected in practice, so that some switches may become entirel y inoperative. As stated, the contact- 8 5 piece cannot be made of copper, because copper is too soft, and yet, on the other hand, it must be made of a metal which is soft enough to be drawn through dies. The cost of casting such small parts of any metal whatsoo ever is prohibitive of such method. It has been the invariable custom hitherto to construct these contact-pieces by drawing a long bar of brass through dies adapted to form a groove throughout the length of the bar, and 5 the bar as thus drawn. was then chopped off into sections, each section constituting a contact-piece provided with its groove or slot, which was then perforated for the reception of the end of the spindle. 1 than brass could be thus drawn without seriously injuring or destroying the dies, and

No metal harder I00 hence it is that brass has been the only mate:

different metals; but owing to the limitation,

:"t the use of brass, as pointed out above, it

was not considered possible to do so.

The prior art discloses one solution of this problem, which consisted in interposing a strip of different metal than brass, such asv phosphorbronze, between the brass contact-piece and the brass sleeve. In this case either the contact-piece or the sleeve could be made entirely of phosphor-bronze, but that would cost more. This greater cost is due not only to the great cost of phosphor-bronze, but also to the fact that bronze, steel, or similar metals are too hard to be drawn in dies without in- ;i uring or destroying the dies, which, of course, takes that method of manufacture out of consideration. I

This invention aims at the root of the. difficulty, which has existed ever since the beginning of the manufacture of modern lampsockets. It obviates the necessity of the use of an intermediate strip of difierent metal in accordance with the method just referred to and renders possible the employment of a contact-piece which is itself constructed of difierent metal from that of which the sleeve is composed, such different metal being preferably steel on account of its relatively low cost. In accordance with'this invention the necessity of drawing the metal v for the contact-pieces through dies i's'obviated, and the,

cams are constrifited of a metal other than ed. on the spindle so as tohave lost motion and to fully carry out the functions of the standard Edison key-type lamp-socket.

Of the drawings, Figure 1 is avertical sec tion of a lamp-socket constructed in substantial accordance with the original patent for the socket and which is almost universally used. Fig. 2 is a perspective viewof a contact-piece as struck up or punched from sheet metal. Fig. 3 is a perspective of the switchspindle provided with a thumb-piece. Fig. 4 is a perspective view of the assembly of the contact-piece and spindle. Fig. 5 is a transverse section through the contact-piece and spindle,showing theirlost-motion connection;

and Fig. 6 is a longitudinal section through the spindle and contact-piece, also showing their lost-motion connection.

The device shown in Fig. 1 is so familiar tov those skilled in the art that it is considered unnecessary to particularly describe any features of it other than those to which the invention has especial reference. These features comprise the spindle, P, which is suitably supported in a U-shaped frame U, its righ t-hand end engaging in an oblong slot L in the frame U, whereby the spindle P can be freely depressed when the end of the contact-piece engages the contact-sleeve. The

spindle has a contact-piece O mounted upon it, and this contact-piece is adapted to be rotated by the spindle when the thumb-piece v H is manipulated in order to make and break the circuit of a lamp retained by the threaded brass sleeve E by bridging across from the upper part of the sleeve to the spring-terminal S. The spindle P and cam are constructed in accordance with this invention, as shownin Figs. 2 to 6, inclusive.

Fig. 2 clearly indicates the shape of the contact-piece, which is punched by suitable dies well known in the art from a sheet of suitable metal, such as steel. As shown, the contact-piece is formed with a non-circular perforation O, which may be punched out-si multaneously with the punching of any contact-piece, or, if desired, may be punchedout before orafterward. The blank contactpiece is oblong or substantially rectangular in outline, except the longitudinal walls D of the perforation or slot 0, which are slightly curved and are relatively thin.

In Fig. 3 is shown the switch-spindle P,-provided, as hitherto, with a thumb-piece II, of suitable insulating material, such as hard rubher. The material feature of this spindle is the portion M, which is relatiyely small with respect to the rest of the spindle.

The operations of producing the contactpiece (shown in Fig. 2) and.the spindle (shown in Fig. 3) may be conducted independently of each other, and when they are completed the contact-piece G is slipped over the end of the spindle, the perforation O of the contactpiece being of such size and shape that the I tip ti lle-can readily pass through it. brass in such manner that they can be mo,unt-- *1 hen vi0ontact-piece is located at the portion M of, hespindle, thehnembers are placed under vsuitable dies, and the side walls D of the slot Qarecomprcssed'together or. swaged, so that the contact-piececannot be withdrawn thereafter fromlthe spindle, but is held att-he reduced portion'ofthe spindle by the relatively large portions of the spindle on opposite sides of the reduced portionl' The two members as thus assembled are shown in perspective vin Fig. 4 as ready to be embodied inthe lampsocket, (shown in Fig. 1,)iexc'ept that in practice the thu mb-piece orhand'lell wi ll,beplaced over the end of the spindle as a last operation. It will be observed that after the wallsD of the contact-piece have been bent inwardly the entire long sides of the contaet-piec are straight. I 1

As shown in Figs. 5 and 6, the con C does not fit the reduced portion of as dle, but the side walls D are compressed sufficiently to hold the contact-piece inplaee The slot 0, even when the side wallsfare'co pressed, is so much larger than the .reduce portion M of the spindle that the contact-piece has sufficient lost motion with respect to the spindle to enable it to be thrown by the spring S, Fig. 1, in breaking the circuit in advance of the movement of the spindle in order to produce a snap action. lVhen the relatively small portion M is formed intermediate the ends of the spindle, as shown, the contactpiece is held at that portion by the adjacent parts of the spindle of greater size, so that the contact-piece is prevented from longitudinal movement on the spindle.

As shown in Fig. 3,when the reduced portion H of the spindle is formed projections N are also thereby formed, which serve the function of the pin of the original patent for the socket. While this device possesses also this advantage, it is to be understood that it is not limited to this specific method, as, in fact, the pin of the original socket patent could be employed in place of the projections N in connection with applicants invention. Neither is it necessary that the reduced portion M should be formed intermediate the ends of the spindle, as it is within the limits of the invention to form the reduced portion at one extremity of the spindle, the latter being combined with the contact-piece (shown in Fig. 2) and mounted bylost motion on the reduced portion of the spindle. VVhatI have invented is a solution of the hitherto baffling problem of making a contact-piece of different metal from that of which the brass sleeve is composed, and the claims are intended to cover all substantially similar means for accomplishing this result.

What I claim as new, and desire to secure by Letters Patent of the United States, is

1. An electric switch, which comprises a spindle having a relatively small non-circular portion, combined with a contact-piece having a non-circular perforation and mounted over the relatively small portion of the spindle, the perforation in said contact-piece being smaller than the larger portions of the spindle on opposite sides of its small portion, whereby the contact-piece is held on the spindle, and said perforation in'the contact-piece being larger than said smaller portion of the spindle, whereby the contact-piece can have lost motion with respect to the spindle;- said non-circular portion of the spindle and noncircular perforation in the contact-piece cooperating to enable the contact-piece to be rotated by the spindle.

2. An electric switch, which comprises a spindle having a portion of relatively small size, combined with a contact-piece mounted over such relatively small portion and having a perforation which is larger than such small portion, so that the contact-piece can have lost motion with respect to the spindle; said spindle being adapted to rotate said contactpiece,

3. An electric switch, which comprises a spindle having a portion of relatively small size intermediate its ends, combined with a contact piece mounted at such relatively small portion, said contact-piece having a perforation which is larger than such small portion of the spindle and smaller than the adj acent opposite larger portions of the spindle, so that the contact-piece is retained at the small portion of the spindle and preventedfrom longitudinal movement; saidspindle being adapted to rotate said contact-piece.

4. An electric switch, which comprises a spindle having a portion of relatively small size, and projections extending therefrom beyond the larger portions of the spindle, combined with a contact-piece mounted on said small portion of the spindle, and having a perforation which is larger than the smaller portion of the spindle, said projections serving,

to rotate the contact-piece when the spindle is rotated.

5. The combination with the rotatable spindle of an electric switch, said spindle having a relatively small portion intermediate its ends, of a contact-piece having a perforation, said contact-piece being held upon the small portion of the spindle by the larger parts of the spindle on opposite sides of the smaller portion, said parts being constructed and arranged so that said contact-piece is rotated by the spindle.

6. The combination withthe rotatable spindle of an electric switch, said spindle having a relatively small portion, of a sheet-metal contact-piece having a perforation and held on the small portion of said spindle by the larger opposite adjacent portions, said parts being constructed and arranged so that said contact-piece is rotated by the spindle.

7. The method of manufacturing an electric switch, which consists in operating upon the rotatable switch-spindle to form a portion thereof of reduced size; placing a perforated contact-piece oversuch reduced portion; and finally swagin g the contact-piece, so that it is held with lost motion on the spindle at the reduced portion thereof.

8. The method of-manufacturing an electric switch, which consists in operating upon the rotatable switch-spindle to form a portion of reduced size; producing by punching, a sheet-metal contact-piece having a non-circular perforation which is larger than the reduced portion of the switch-spindle, and swaging the contact-piece upon the reduced portion of the spindle so that the parts will have a lost-motion connection.

9. The combination with the rotatable spindle of an electric switch, said spindle having a relatively small portion, of a contact-piece having a perforation held on the small portion of said spindle by the larger opposite adjacent portions.

In witness whereof I have hereunto set my hand this 27th day of May, 1901.

GEORGE E. PAINTER.

Witnesses:

BENJAMIN B. HULL, MARGARET E. WOOLLEY.

IIO 

